1. Field of the Invention
The present invention relates generally to a method and apparatus for placement of fertilizer and seed during planting of an agricultural crop. More specifically, the present invention concerns a fertilizer injector wing that affixes to a seed boot of a low disturbance disc opener and a method of using the winged opener to place a seed row and a dedicated band of fertilizer at an optimum geometric positional alignment relative to the seed row. The inventive wing and method of use enables a toxic charge of fertilizer (e.g., a charge containing the entire nutrient package to sustain season long growth) to be placed in close proximity with the seed row in a single, relatively high speed, low soil disturbing planting pass of relatively simple, durable equipment without damaging the germination of the seed or disrupting the seed bed.
2. Discussion of Prior Art
Farmers are increasingly utilizing no-tillage planting techniques to produce all types of crops. No-till planting typically utilizes a rotatable disc opener, or drill, that fractures the soil into a furrow thereby creating a disturbed soil zone wherein a seed bed can be formed for seed placement therein, prior to closing the furrow. The disc opener is designed to minimize the soil disturbance leaving the stubble, or organic matter, from the previous crop standing in the field, which in turn reduces water runoff in the field, thereby greatly reducing erosion of the top soil. The furrow opening, seed bed formation, seed placement, and furrow closing are typically done in a single pass with a disc opener that includes a rotatable disc, a seed boot, and a closing wheel. Prior art low disturbance disc openers are well known in the art and are available from most OEMs. One exemplary no-till disc opener is the John Deere 1890 No-Till Air Drill.
While no-till farming greatly reduces the escape of CO2 by reducing the mineralization of the organic matter in the soil, it also undesirably prevents the release of organic nitrogen into the soil, which is needed by the new seedlings in order to grow. It is known in the art to add an ammoniacal fertilizer to the soil, either with a pre-planting application of fertilizer or applying fertilizer at the time of planting, in order to enhance the yield of the produced crop. The most prevalent ammoniacal fertilizer utilized is anhydrous ammonia, however, it is known to use other ammoniacal fertilizers including aqua ammonia, ammoniac based liquified urea, and other ammoniac based solutions such as Solution 32 (32-O-O), Solution 28 (28-O-O), etc. It is also known to add other, less toxic fertilizers to the soil as well as other control agents, in addition to the ammoniacal fertilizer such as ammoniated phosphate (e.g., 10-34-O, etc.), potassium, sulfur, mustard meal, etc. These fertilizers and agents can be dual placed with the ammoniacal fertilizer, through processes known as double or triple shooting, or can be independently placed after the ammoniacal fertilizer is placed.
Prior art no-till fertilizer placement methods include top dressing the fertilizer and banding the fertilizer. Top dressing, or broadcasting, typically sprays the fertilizer on top of the field prior to planting or over the crop after the seedlings have sufficiently grown above the surface. However, top dressing does not involve placing the fertilizer in the top soil. Banding the fertilizer involves placing the fertilizer in a specified location in the ground either prior to planting, during the planting process, or after the seedlings have sufficiently grown above the surface. Prior art banding methods include mid-row banding, paired row banding, and cross row feeding. Mid-row banding requires an additional opener, dedicated to the fertilizer, to open a furrow between two seed rows, where the fertilizer is placed. Seed rows must be typically spaced ten inches a part, with the mid-row band being five inches from each seed row. An exemplary mid-row banding opener is the John Deere 1895 Separate Fertilizer Placement Tool. Paired row banding also requires an additional, dedicated opener to create a separate furrow for the fertilizer, however, a pair of seed rows are spaced closer together, for example, five inches apart, with the fertilizer band placed between the paired row, and adjacent groups of paired rows are further spaced, for example fifteen inches apart. In cross row feeding, a deep band of fertilizer (e.g., six inches below the surface) is placed beneath each seed row and the seed rows are placed close together, for example three and one-half inches apart. In order to obtain the deep banding, cross row feeding requires either a dedicated opener for the deeper fertilizer furrow or a knife positioned behind the opener disc for placing the fertilizer deeper than the seed row. An exemplary cross row feeding opener is disclosed in U.S. Pat. No. 5,140,917 (the “Swanson '917 patent”) issued to the inventor of the current application and incorporated herein by reference. Although not technically considered banding, it is also known to place non-toxic amounts of popup fertilizer in the seed row during planting and then subsequently place the toxic charge in the soil after the seedling has sufficiently grown, for example, by side dressing. One exemplary device to place popup fertilizer in the seed row is disclosed in U.S. Pat. No. 6,453,832.
These prior art no-till fertilizing methods are problematic and subject to several limitations. For example, with both mid-row banding and paired row banding, each fertilizer row must be shared by at least two seed rows thereby reducing the effectiveness of the fertilizer available to any one row and thus undesirably diminishing the yield. Mid-row banding is further problematic in that the fertilizer must be remotely placed from the seed rows thereby undesirably allowing weeds exposed along the fertilizer furrow better access to the band than the remote seed rows. These problems were identified and discussed in the Swanson '917 patent previously incorporated herein. Although cross row feeding was an advance in the art and solved many of the problems discussed above, cross row feeding, like all of the prior art banding methods, require separate openers, or deep running knives, to cut the opening for the fertilizer bands. This additional cutting equipment is undesirable for several reasons, including increased purchase and maintenance costs, increased horsepower requirements to pull the cutting equipment, and increased weed-activating and erosive soil disturbance. Furthermore, excessive soil disturbance is undesirable because it exposes moisture rich top soil to the atmosphere thereby allowing the moisture to be lost and thus unavailable to the germinating seed. Moreover, it has been determined that, when deeply placed, the toxic ammoniacal charge undesirably migrates with wetting front line and undesirably away from the germinating seed roots. Placement of popup fertilizer in the seed row is problematic as it requires at least two equipment passes through the field and undesirably prevents the seeds access to the toxic charge of fertilizer during the critical germination stage thereby limiting yield. Accordingly, there is a need for an apparatus and/or method of planting that allows producers to place a dedicated toxic charge of ammoniacal nitrogen and phosphate in the soil during planting at an optimum position relative to the seed row using efficient equipment that does not disturb the soil seed bed or create excessive soil disturbance.